The gas burner of radiant heating type is a gas burner in which a heating object is heated, and cooked with a radiant wave from a heated radiant body caused by combustion of mixed gas of fuel and air.
FIG. 1 illustrates a perspective view of an example of a related art gas oven range employing gas burners of radiant heating type, and FIG. 2 illustrates a diagram showing a system of a gas burner of radiant heating type in the gas oven range.
The related art gas oven range is provided with an oven part 100 for barbecuing or baking by using direct heat and heat convection, a grill part 200 over the oven part 100 for grilling fish to brown by using heat convection, a top burner part 300 over the grill part 200 for heating food or a container containing food, and a back guide part 400 in rear of the gas oven range for discharging exhaust gas from the oven part 100, the grill part 200, and the top burner part 300.
The top burner part 300 is provided with a plurality of burner assemblies 310 in a housing (not shown), and a ceramic glass plate 302 on top of the housing 301 for closing tops of the burner assemblies 310.
Referring to FIG. 2, the burner assembly 310 is provided with a burner housing 311 closed with the ceramic glass plate 302 to form a burning space, a burner chamber having a burner pot 312 mounted on an underside of the burner housing 311 for mixing gas and air, and a burner mat 313 on top of the burner pot 312.
In general, closed with the ceramic glass plate 302, the burner assembly 310 of radiant heating type has no natural air supply from an outside of the burner assembly 310, and is involved in shortage of combustion air.
To cope with this in the related art, for supplying mixed gas of fuel gas and an adequate air into the burner pot 312 of the burner assembly 310, the burner pot 312 is provided with one side in communication with the mixing tube 390, and the mixing tube 390 is provided with a gas nozzle 391 connected to a middle part thereof for spraying fuel gas, and a fan 392 and a fan motor 393 at an end thereof for enforced supply of air, for supplying fuel gas and air through the mixing tube 390.
However, the enforced supply of air and fuel gas to the burner pot 312 through the mixing tube 390, resulting to supply air at a fixed air flow rate thereto with the fan 392, causes a problem in that flame can not be controlled as desired because the air flow rate cannot be controlled according to variation of gas supply rate.
Therefore, the related art burner assembly controlled the air flow rate according to variation of gas supply rate, by using a BLDC motor as the fan motor, of which speed is variable, and providing a sensor for detecting user's operation of flame control knob, for varying rotation speed of the fan according to the operation of the flame control knob, to control the air flow rate.
However, in this case, the use of a plurality of expensive BLDC motors pushes up a cost of the burner assembly, and the additional fitting of the flame control knob and the like results to a complicated structure, together with difficulty in control.
In the meantime, U.S. Pat. No. 6,076,517 discloses gas burners of radiant heating type, in which a chamber is provided in a housing of a top burner part, which is in communication with a mixing tube of each burner, and a fan is provided for forced supply of external air to the chamber, to build up a high pressure inside of the chamber, and introduce air into the mixing tubes, for supplying adequate combustion air.
However, since the gas burners of radiant heating type has a system in which the air is supplied to the chamber forcibly through a mixing tube of each gas burner alike above gas burners of radiant heating type, the gas burners of radiant heating type require to vary an air flow rate to the chamber for controlling the air flow rate according to the gas supply rate to the gas burners, resulting to require expensive a variable speed motor such as the BLDC motor as a fan motor for driving a fan, as well as a sensor for automatic sensing of an extent of gas supply rate control.
Moreover, since control of an air flow rate to each burner is very difficult in a case a plurality of gas burners are used at the same time, the gas burners of radiant heating type have structural problems in that a fan and a fan motor are provided to every gas burner individually, or opening of a passage therein is controlled individually.